title: Two Positions of Potassium in Chemically Doped C(60) Peapods: An in situ Spectroelectrochemical Study.
abstract: The state of doping of fullerene peapods C60@SWCNT treated with K vapor was studied by in situ Raman spectroelectrochemistry. For all samples under study, a heavy chemical n doping was proved by the vanishing of the radial breathing mode and the downshift of tangential displacement mode. The K-treated peapods remain partly doped even if they are exposed to humid air. The Ag(2) mode of intratubular fullerene in K-doped peapods in contact with air was still redshifted as referred to its position in pristine peapods. Potassium inserted into the peapods is the reason for the air-insensitive residual doping, which can be removed only by electrochemical oxidation. This indicates the presence of two positions of potassium in doped sample.
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-18223 Prague 8, Czech Republic, and Institute of Solid State and Materials Research, Helmholtztstr. 20, D - 01069 Dresden, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Kalbac
authors.forename: Ladislav
authors.initials: L
authors.lastname: Kavan
authors.forename: Markéta
authors.initials: M
authors.lastname: Zukalova
authors.forename: Lothar
authors.initials: L
authors.lastname: Dunsch